KR100544788B1 - Optical recording media and apparatus and method for forming and recording / reproducing teeth - Google Patents

Abstract

The present invention provides an optical recording medium in which a wobble signal having a period is recorded along all tracks of a header area having a data recording area and an optical recording medium positional information, and a signal bent from the optical recording medium recording medium is disconnected. The present invention relates to an apparatus and a method for recording data input while reading and tracking using the same, and for reading a recorded signal. It is recorded in a bent form, and a bent form is formed by reversing the phase so as to recognize the section discriminating signal with the header area back and forth, and the tracking device using the same is different from the sum signal of the left and right wobble signals respectively filtered by the low pass filter. An adder for generating a signal; A multiplier for multiplying the sum signal and the difference signal to output a tracking error signal; A tracking compensator for generating and outputting a compensation signal for compensating the multiplied tracking error signal; And an optical pickup driving unit for driving the position of the optical pickup according to the compensation signal, further reducing the track length of the header area and relatively increasing the track length of the recording surface, thereby further improving the recording density of the signal. It is a very useful invention that enables stable and accurate tracking without interruption of tracking over the track.

Description

Optical record carrier and apparatus and method for forming and recording / reproducing it

The present invention relates to a recordable optical recording medium, and an apparatus and method for forming and recording / reproducing the same. More particularly, the present invention relates to a track along an entire track of a header area having a data recording area and optical record medium position information. An optical recording medium having a wobble signal recorded therein and an apparatus and method for forming and recording / reproducing the same.

Optical recording media have become more common as CDs are becoming more popular, and DVD (Digital Versatile Disc) standards are becoming more expected. Optical recording media include CD-Rs and DVD-Rs that can be written once, in addition to CD-ROMs and DVD-ROMs for exclusive use of reproduction, and standard discs such as rewritable CD-RWs and DVD-RAMs have been proposed.

The DVD-RAM, which is currently proposed and prototyped in a certain size, has a data area A for recording / reproducing user data and an optical recording medium as shown in some tracks shown in FIG. It consists of a header area B for distinguishing the position information and the subsequent recording surface (Land / Groove), and the convex surface (hereinafter referred to as land) and the concave surface (hereinafter referred to as groove). On the optical recording medium in which the boundary wall C of the land / groove of the data area having the shape of the data region is meandered and rotates at a constant angular velocity, the shape of the boundary wall C is fixed by the reflected light after the incident. It is detected as a signal and used as a synchronization signal for data detection.

In addition, in order to record and reproduce the recordable optical record carrier formed as described above, the optical pickup must travel accurately in the track of the data area. For this purpose, a conventional push-pull method is used. In the method, the data area is tracked by a method of compensating for the error signal using the difference amount of the DC component of the amount of light detected by the left and right photodetection diodes as the tracking error signal.

In the header area, a pre-pit is recorded for position information on the optical recording medium, and the recording surface of the data area is formed with the same land, land, or groove and groove with the header area before and after. Before and after the specific header area, the land and the grooves are converted. In the conventional push-pull tracking method, it is necessary to recognize the shape of the recording surface following the header area. The left and right prepits of the traveling route were recorded separately by crossing back and forth on the header area according to the following recording surface shape. That is, as shown in Fig. 1, when the track of the data area after the header area is a land, the prepits are recorded at the front end on the left side and on the rear end on the right side in the advancing direction of the track. When the track of the data area is a groove, prepits are recorded at the rear end at the left side and at the front end at the right side.

When tracking is performed to record data to or reproduce data from the DVD-RAM formed as described above, the amount of difference signal of the light detection amount of the left and right photodiodes due to the difference in the position of formation of the prepits as described above. If the negative (-) becomes different in the header area section, and the recording surface leads to the groove (1 in Fig. 1), if the difference signal is inverted from negative (+) to positive (+), the recording surface is landed. (2 in FIG. 1), the difference signal is inverted from positive (+) to negative (-), thereby detecting the data recording surface after the header area and detecting the light detection amount of both sides detected in the corresponding recording surface. By reversing the direction of adjustment of the optical pickup relative to the error amount, accurate tracking can be performed to record and reproduce data.

However, the recordable optical recording medium configured as described above has a header for the prepits for the position information on the optical recording medium in order to recognize the device whether the data recording surface is land or groove and correct the tracking direction as shown in FIG. By recording separately at the front and rear ends of the area, besides the prepit recording space for actual position information, a space of non-recorded signal is required, thereby reducing the length of the recording track on which data is recorded / reproduced. This causes a problem of lowering the recording density of the optical recording medium.

In addition, the conventional push-pull method uses the difference in the direct current component of the amount of light detected by the left and right photodiodes to determine and compensate the traveling track deviation of the optical pickup, thereby causing the positional deviation of the objective lens of the optical pickup. This is reflected as the DC amount of the detected optical signal, and even when the optical pickup travels along the normal path, the change of the DC value difference continuously occurs, and the position of the optical pickup is finely calibrated to compensate for this. On the contrary, there is a problem that tracking becomes unstable, and in this case, even when the optical pickup does not form a vertical angle with respect to the surface of the optical recording medium and there is a tilt phenomenon that is slightly inclined with respect to the vertical surface. There was a problem that occurred.

In the conventional push-pull method, tracking is controlled such that the DC value difference between the detected light amounts of the left and right photodiodes becomes zero. Even when the recording path is accurately driven by normal tracking, as shown in FIG. When passing through the formed header area, the DC value of the left and right detection light amount is different, and this value is changed rapidly at the front end and the rear end of the header area. Because of the large vibration, the probability of an error occurring in the signal reproduction of the subsequent header area and the subsequent data area entry is increased.

Therefore, the conventional push-pull servo control determines the shape of the subsequent recording surface from the signal detected in the header area and does not use it as an error amount for tracking. In the header area, the header amount is maintained just before the header area. Servo control is performed to compensate for the amount of error maintained until the area passes, but this tracking control is independent of the actual path deviation amount in the header area. It takes a long time to detect this in the area and compensate for the normal driving path, and thus there is a great problem that an error occurs in recording or reproducing the data in the data area entry.

Accordingly, the present invention was created to solve the above problems, and forms a recordable optical recording medium which can improve recording density and provide more stable tracking during recording / reproducing, and also records / records a signal thereto. It is an object of the present invention to provide an apparatus and method for reproducing.

In the optical recording medium according to the present invention for achieving the above object, a header area formed between recording areas in which a bent signal having a period is recorded is recorded in a bent form, and distinguishes concave and convex surfaces of a subsequent data area. In order to do this, it is characteristic that only the recording pit is recorded without having a separate margin space on the header area.

The optical recording medium forming apparatus and method according to the present invention are bent to form a laser beam incident on a photo-resisit even when the header signal is formed, so that the header signal recorded in the header area is recorded in a bent form. Characterized by deflection according to the period of the signal,

An apparatus and method for recording / reproducing an optical recording medium according to the present invention identify a header area in which position information of an optical recording medium is recorded according to a specific change of a bent signal detected in the data area and the header area, and reference the identification point. Recording a signal in the data area or detecting a signal recorded from the data area,

An apparatus and method for recording / reproducing an optical record carrier according to the present invention is characterized in that tracking of an optical pickup is performed according to a bent signal component which is continuously detected in the data area and the header area so that the tracking is not interrupted. It is.

Hereinafter, a recordable optical recording medium recording medium according to the present invention, an apparatus and method for forming the same, and a tracking device and method for recording and reproducing a signal on the optical recording medium recording medium and accurately driving the tracks An example will be described in detail with reference to the accompanying drawings.

FIG. 2A shows a partial region of the optical recording medium according to the present invention, and unlike the conventional optical recording medium format of FIG. 1, it shows that the recording feet of the header area B are recorded in a curved shape with respect to the center line of the track. Giving.

Fig. 2A shows a form in which lands and grooves are switched (so-called 1-spiral type discs) before and after the header area B, where signals detected from the curved surface of the data area and from the curved shape of the header area B are shown. In order to have continuity, in the case where the land is connected to the header area, the recording feet on the header area are formed in a phase inverted from the bent shape on the land, and in the grooves after the header area, the bent shape of the header area is formed. It is formed into a phase following the phase.

When formed as described above, the amount of signal detected from the photodiode on the right side in the advancing direction, when viewed from the center line (ll line) of the upper bent shape of the land, increases the land portion, so that the light beam is reflected in the increased area. The arc compensates the reflected light of the center region by the phase difference according to the optical path difference (depending on the condition, the phase difference may cancel the reflected light of the center region, in which case the amount of detection light decreases as the land region increases) Since the amount of light is increased, when it reaches the header area, it increases from the minimum point to the sinusoidal point and reaches the p1 point, and the signal level of the reference level is obtained. The light reflection at this time increases sine- ally conversely, and when the point P2 on the header area is reached, After a good run, it begins to decrease again. At the point (p3) where the maximum amount of detected signal is returned to the signal level at the reference level, the groove is continued to the groove-like recording surface. In the groove, the land area adjacent to the groove is started from the boundary portion following the header area. Since sine increases, the amount of signal detected therefrom also increases sine.

Based on the above principle, the signal amount detected on the left side of the traveling path when passing the upper track (track to the groove-to-groove) of FIG. 2A, except for the DC component, is continuously shown in FIG. Subsequent sinusoidal waveforms, i.e., wobble signals, are detected, and the AC component of the signal amount detected on the right side of the traveling path is detected in the inverted phase as shown in FIG. 2B, which will be described in detail later.

In the track transitioned from the groove to the land shown in the lower part of Fig. 2A, the wobble signal is continuously inverted from the bent shape of the recording feet of the upper header area so that the wobble signal continuously connected without phase change can be detected by the above-described principle. It is recorded in a bent form.

In the description of Fig. 2A, the curved shape of the recording pits recorded on the header area is one cycle. However, in the case where only the phase shift point with the recording surface that follows before and after coincides without the phase change as described above, the curved cycle It is okay for numbers.

Fig. 3 shows a form (so-called 2-spiral type disc) in which the land and the grooves are not switched back and forth to the same recording surface with the header area B in front and back. The bent shape of the recording surface following the header area is formed to be inverted from that of Fig. 2A.

4 is to prevent the wobble signal detected left and right from bent recording feet as the optical pickup proceeds through the header area, and may be disturbed by the amount of change in reflected light caused by the bent recording feet on the header area of adjacent tracks. As another embodiment of the recordable optical recording medium according to the present invention, wherein the bent recording feet between adjacent tracks are separated from each other back and forth on the header area so as not to form the recording feet on adjacent tracks of the bent recording feet. Fig. 4B shows a case where lands and grooves are switched back and forth, while Fig. 4B shows a case where lands or grooves are not switched and continue in the same recording surface form.

In the embodiment of Fig. 4, when an optical pickup passes an area where no prepit is recorded on the header area, a sine signal corresponding to the wobble signal detected from both prepits recorded in a bent form on adjacent tracks. In the non-recorded area of the prepit, tracking may be performed by the wobble signal described in detail below, or according to the magnitude of the left and right signals detected from the curved recording feet of the adjacent tracks detected. It is also possible to hold the error amount of and to perform the tracking during the interval according to the amount.

FIG. 5 shows a part of a track in which a header section recognition signal is formed with a bent phase reversal in front of and behind the header area in order to facilitate recognition of the header area of the optical recording medium according to the present invention. The phase inversion point P1 for indicating the start of the header area is formed in the data area in front of the predetermined section of.

As shown in Fig. 5, when there is a phase inversion for notifying the header region section in advance, there is a phase inversion for notifying the end of the header region, which is realized in the interface between the header region and the data region. . That is, since the bent signal formed in the grooves and lands after the header area is inverted unlike in FIG. 2A, the signal detected by the above-described principle is started in phase inversion with the signal in the header area. By detecting, the end of the header region section is recognized. An apparatus and a method for recognizing the formed header region section and outputting the header section signal according to the same will be described in detail later.

6A and 6B illustrate a part of a track according to another embodiment having the header region section recognition signal as described above. Unlike FIG. 5, the boundary of the header region is formed without forming a separate phase inversion point in the data region. By reversing the phase of the bent signal detected back and forth, the header area is recognized therefrom. Accordingly, the shape in which the recording feet of the header area in FIG. 6A are bent is inverted in phase from that in FIG. 2A, and the shape in which the recording feet in FIG. 6B is bent is inverted in phase as in FIG. If the recording pits of the header area are formed as described above, the phase of the wobble signal detected with the header area as the boundary is inverted according to the above-described principle, so that only the header area can be directly recognized.

Figure 7 shows an embodiment of an apparatus for forming an optical record carrier according to the present invention, comprising: a laser (10) for generating a laser beam; A collimator (11) for aiming the generated laser beam into parallel light; A translucent mirror 12a for changing the path of the parallel light; and a reflection mirror 12b; Optical modulators (13a, 13b) for selectively blocking / transmitting each of said path-changed parallel lights by a signal corresponding to a shape of a recording surface to be formed and a recording pit signal to be formed in a header area; A wobble forming signal generator 20 generating and outputting an ultrahigh frequency signal whose frequency is changed according to a wobble signal having a predetermined period; Optical deflectors (15a, 15b) for deflecting the advancing direction of each light selectively transmitted and reflected by the reflection mirrors (14a, 14b) according to the frequency shift of the generated high frequency signal; Semi-transparent mirrors and reflecting mirrors (16, 16a, 16b) for synthesizing each of the light deflected by the traveling paths by reflection and transmission to be redirected to a photoresist to form a mask of the optical record carrier; And a condenser lens 17 for condensing the incident light which has been changed in the final path with a photoresist.

In the optical recording medium forming apparatus configured as described above, the laser beam emitted from the laser 10 is first converted into parallel light by the collimator 11 to be incident on the translucent mirror 12a, and the semi-transparent mirror 12a reflects a part of light and directly enters the light modulator 13a, and transmits a part of light to enter the light modulator 13b by reflection of the reflecting mirror 12b at the rear end.

On the other hand, the optical modulator 13a has an ultra-high frequency signal of about 240 MHz or more for determining the shape of the recording surface of the optical recording medium, that is, the land (convex surface) and the groove (concave surface), as shown in FIG. Is applied to the other optical modulator 13b so that an on / off signal of a very high frequency corresponding to the recording feet to be recorded in the case of the header area is applied as shown in Fig. 8, wherein the respective optical modulators 13a, 13b) changes the diffraction angle of the crystal in accordance with the presence or absence of the application of the ultra-high frequency signal to transmit or block the incident light, and the transmitted light is reflected by the respective reflection mirrors 14a and 14b to reflect the light. Incident on the deflector 15.

In addition to the selective transmission of the optical signal as described above, the wobble signal generator having a constant period as shown in Fig. 8 is continuously applied to the wobble signal generator 20. 20) shifts the frequency of the generated ultra-high frequency signal of about 240 MHz or more according to the magnitude of the sine wave signal of a certain period to be applied to the optical deflectors 15a and 15b. The period of the wobble signal shown by way of example in FIG. 8 is assuming that the wobble signal has two cycles during the header signal recording in order to have the shape of the recording feet bent twice during the header area period.

When the frequency of the ultra-high frequency generated and applied by the wobble forming signal generator 20 changes, the diffraction angles of the crystals of the optical deflectors 15a and 15b become slightly deformed at the angles through which light is transmitted, thereby advancing the transmitted light. The direction is deflected depending on the signal size of the sinusoidal wave.

Each light selectively transmitted by the above-described process and whose direction of travel is deflected according to the applied sine wave signal is synthesized by the reflection mirror 16a and the semi-transparent mirror 16, and the reflection mirror 16b. By incident light into the condenser lens 17, the light is selectively transmitted through a stamper having a photoresist formed on a glass disc, which is rotated at a constant angular velocity, and condensed by a sine beam. The register is melted, so that its position is changed sine, i.e. wobble, during the formation of the groove-like recording surface along the track, as well as during the formation of the recording area of the header area. A stamper having a header signal recorded in a form is formed, and a recordable optical recording medium according to the present invention can be manufactured using the stamper thus formed. Will.

Fig. 9 shows an approximation of a curved view of a part of an arbitrary track including a plane and a header area of the optical record carrier according to the present invention produced according to the above-described process.

FIG. 10 shows a schematic configuration for tracking an optical recording medium according to the present invention in which a track is formed as shown in FIG. 9 and for reproducing a signal based thereon, wherein a recordable optical recording medium (DVD-RAM) ( An optical pickup 1 for recording and reproducing a signal from the DR); A control signal generator 100 for converting an optical signal detected by the optical pickup 1 into an electrical signal to separately amplify a low frequency wobble signal and a high frequency data signal and output a tracking error signal based on the wobble signal; A reproduction signal processing unit 110 for filtering and outputting the amplified high frequency data signal to restore original recording data; And a tracking control unit 200 for controlling tracking of the optical pickup 1 by using the output tracking error signal.

In the playback apparatus having the configuration as shown in Fig. 10, in order to read a signal from an optical recording medium or to record a signal on the optical recording medium, the optical pickup 1 must accurately track the signal recording track. A tracking apparatus and method having improved tracking characteristics using an optical record carrier according to the present invention will be described in detail.

FIG. 11 is a detailed configuration diagram of a servo system showing the signal amount generation for tracking control in detail in FIG. 10, and detecting the left and right reflected light at the center of the track and converting them into electrical signals. Photo detectors PDa and PDb; Low pass filters (101a, 101b) for respectively passing a wobble signal band in the converted left and right electrical signals; A high pass filter (102a, 102b) for passing a high frequency signal (RF) band corresponding to a data signal in the converted left and right electric signals; An adder 104 for generating a sum signal and a difference signal of the left and right wobble signals respectively filtered by the low pass filters 101a and 101b; and a subtractor 103; A slicer (106) for shaping the difference signal into a pulse shape; An edge detector (107) for detecting an edge of the output pulse of the slicer (106); A phase lock unit (PLL: Phase Lock Loop) for outputting a phase synchronized pulse at an edge detection point of the edge detector 107; A divider (109) for dividing the phase-locked pulse of the phase synchronizer (108) by two; A multiplier 105 which multiplies the sum signal and the output signal of the divider 109 and outputs a tracking error signal Te; A tracking compensator 201 for generating and outputting a compensation signal for compensating the multiplied tracking error signal; And an optical pickup driver 202 for driving the position of the optical pickup 1 according to the compensation signal.

Fig. 12 shows signal waveforms in the main part of the servo system in Fig. 11, and Figs. 13A to 13C show signal waveforms in the main part in the servo system of Fig. 11 performing the tracking operation. The signal change in the header area, which is a boundary area between the land and the groove, is omitted.

12 and 13A to 13C, the left and right light detection signals (1, 2 and 3, and 3 and 3 waveforms in Figs. 13A to 13C, and Fig. 12 waveforms) are bent on the interface with the neighboring tracks of the optical recording medium according to the present invention. Is for the case of mutual in phase as shown in Fig. 13A, in this case, the left and right photodetection signals are outputted with their phase reversed.

FIG. 14 is a diagram illustrating a principle in which the left and right light detection signals are inverted in phase. When the optical recording medium is rotated and the optical pickup travels along the center track, the left and right reflected light are rotated by one period shown in FIG. At each point of P1, P2, P3, P4, and P5, the mutual increase and decrease reverse.

That is, when viewed from the center line of the traveling path, the light reflected from the width of the left and right fluctuation areas of the land (or groove) that is changed in the path due to the curved shape reinforces the light reflected from the path center area. In the case where the recording medium is formed or a photodetecting optical system or the like is formed, the intensity of the detection light becomes large when the corresponding area (land or groove) is increased. Instead of decreasing the area and decreasing the intensity of the detection light, the land area increases on the right side and the intensity of the detection light increases. At the point P2, the detection light on the left is the lowest and the detection light on the right is the maximum. When passing through the point P3 again, the amount of mutual detection light becomes the same, but the left detection light is switched from negative to positive based on a constant DC level, while the right detection light is positive. Since it is converted to negative (-), the detection light on the left and right sides of the AC component except for the DC component is detected by inverting mutual phases. The phase inversion of the left and right photodetection signals based on this principle causes the optical pickup to travel the land recording surface. Even if the same.

The above description with respect to FIG. 14 is made up of conditions under which light reflected by the left and right fluctuation area widths (or grooves left and right fluctuation area widths) of the land to be changed is complemented with light reflected near the path center line as mentioned above. Unlike the above assumption, when the light reflected at the left and right fluctuation range widths is configured to cancel the light reflected near the path center line, the waveforms corresponding to the detection light shown in the upper and lower portions of FIG. All will appear in reversed form.

Hereinafter, the operation of the servo system of FIG. 11 will be described in detail with reference to the waveform diagrams of the principal portions of FIGS. 12 and 13A to 13B.

First, assuming that the optical pickup travels exactly at the center of the signal track as shown in FIG. 13A, a plurality of wobble signals such as 1 and 2 of FIG. 13A output from the low pass filters 101a and 101b are described. When the adder 103 and the subtractor 104 output a difference signal as shown in ③ in FIG. 13A and a sum signal as shown in ④ in FIG. 13A, the tracking is accurately traveling along the center line of the recording surface. Since the left and right wobble signals have the same magnitude and the opposite phases, the sum signals of the two signals are zero, and thus are multiplied and output irrespective of the output signal of the divider 109 which is another input signal of the multiplier 105. The tracking error signal Te becomes 0 and is applied to the tracking compensator 201. Accordingly, the tracking compensator 201 maintains a normal tracking state by not outputting a compensation signal.

On the other hand, the subtracted output signal of the left and right wobble signal of the subtractor 104, as well as normal tracking, as shown in Figure 13b and 13c, the optical pickup is slightly deviated to the right or left in the center track, so that the center of the incident beam Even if it is biased to the right (Fig. 13B) or to the left (Fig. 13C) in the advancing direction, the amount of change of the signal detected by the photodiode PDa or PDb on the side where the center of the incident beam is biased is closer to the bent boundary surface. The amplitude of the change amount of the signal decreases as shown in ② of FIG. 13B and ① of FIG. 13C on the groove recording surface (decreases or increases, whether the progress recording surface is a land or a groove, and a bent shape is a land or groove when progressing. It depends on whether the reflected light on the plane of the region of change has a phase difference that complements or cancels the central reflected light. When the recording surface is advanced, it is assumed that the amount of change in the detection signal amount on the side where the optical pickup is biased decreases, and under this assumption, the amount of change in the light detection amount on the side where the optical pickup is biased becomes larger when the land recording surface is advanced. In the examples of the waveform diagrams of 13a to 13c, the traveling track of the optical pickup is slightly displaced because the side where the center of the incident beam is farther apart from the bent interface, so that the amplitude of the variation of the detected signal increases relatively more. Even if the incident beam is biased left or right, the magnitude of the signal detected by the left and right photodiodes PDa and PDb increases on the other side by an amount that decreases on one side, and thus the subtracted output signal of the two phase inverted signals is almost changed. Is the same size (3 in FIGS. 12, 13a, 13b and 13c) without

However, the point where the left and right wobble signals detected from the optical recording medium are inverted in phase, such as the phase inversion point in the optical recording medium formed such that the wobble is inverted in phase when the land and the groove are switched back and forth in the header area (FIGS. 12 and 13). PS point), the phases of both signals applied to the subtractor 103 are inverted while the magnitudes of the change widths of the left and right detection light are inverted due to the change of the recording surface (before and after the PS point waveforms in Figs. 13A to 13B). The difference signal, which is the output signal of the subtractor 103, is phase-inverted and output at the corresponding position PS, and the sum signal output from the adder 104 is output as a continuous sine wave without a phase change.

The output pulse of the slicer 106, which pulses the sine wave signal of the subtractor 103 by the reference slice level, does not change state at the position PS where the phase is reversed as shown in FIG. Will continue to be maintained. That is, if the previous value was logic 1 (logic 0), the value of logic 1 (or logic 0) is still maintained even after the phase shift position PS.

As such, the signal shaped into pulses by the slicer 106 is applied to the edge detector 107 to detect the transition of the state, that is, the transition point of the logic value, each time the edge detector 107 is shown in FIG. As shown in FIG. 12, a pulse having a predetermined width is output to inform the timing of switching the output pulse of the slicer 106. At the position PS where the phase of the wobble signal is inverted by this operation of the edge detector 107, since there is no change in the state of the input signal, no pulse is outputted, and thus, a predetermined period (two times the wobble signal). One is missing from the pulse train output.

However, the output signal of the phase synchronizer 108 outputting a pulse of 50% duty ratio phase-locked to the output pulse of the edge detector 107 before the phase inversion time PS is shown in FIG. Similarly, even if a pulse of the input signal is missed, the output is continuously output as a signal of a previously tuned phase, and when the pulse is input thereafter, the output pulse is tuned again. The pulse of the period is continuously and continuously output, and this signal is divided by the divider 109 so that a stable amount as shown in Fig. 12 'of FIG. 12 without phase inversion at the same period as the detected wobble signal. It will change to a negative pulse.

In the case of the normal pickup along the path center as in the case of the optical pickup described above, the sum signal of the adder 104 is always 0, so it is multiplied by the output of the divider 109 outputted as ③ 'of FIG. Even if the signal is lost, there is no change in the signal value, thereby maintaining a stable tracking state.

However, the sum signal when the traveling path of the optical pickup is separated from the center to the right and the left signal is larger than the signal detected from the right (④ in FIG. 13B) is a signal that is separated from the center to the left and the right signal is detected on the left side. The phase signal is inverted from each other when the sum signal ④ of FIG. 13C is larger, and the sum signal becomes a continuous sinusoidal wave without changing the phase as described above even after the phase inversion position PS of the detected wobble signal. After the phase inversion point, the sum signal at the left and right side departures still has the phase inverted with each other.

That is, in the waveform diagram of the embodiment of Fig. 13, when the optical pick-up is displaced from the center to the left, the sum signal has the output pulse ③ 'and the positive (-) switching of the frequency divider 109. On the other hand, when the optical pickup is driven from the center to the right (④ of FIG. 13C), the sum signal is output pulses ③ ′ and positive (−) signals of the divider 109. The switching point becomes the inverted phase signal ④ of FIG. 13B, whereby the signal multiplied by the multiplier 105 may be greater than or equal to the reference level DC 0 (⑤ in FIG. 13C) or less (FIG. It becomes the signal of full wave rectification of ⑤) of 13b.

The multiplication signal generated through the above process, that is, the tracking error signal Te is applied to the tracking compensator 201 and averaged, and converted into a DC signal as shown in FIG. 13A, 13B, and 13C. Since the difference of the sum signal of the adder 104 increases as the amplitude of the multiplied signal of the full-wave rectified form increases from the center of the tracking, the amplitude of the output pulse of the divider 109 is kept constant. The amplitude of the multiplication signal (5) in Figs. 13B and 13C is proportional to the amount of deviation, and the level of the DC signal averaging the multiplication signal reflects the amount of deviation from the center track. Accordingly, the tracking compensator 201 generates a compensation signal necessary to cancel the DC level obtained from the averaging of the multiplication signal and applies the compensation signal to the optical pickup driver 202, and the optical pickup driver 202. The optical pickup drives and adjusts the position of the optical pickup at a pre-adjusted proportional ratio according to the applied signal, so that the optical pickup returns to the normal driving track and maintains driving of the center track.

The tracking method using the wobble signal according to the present invention as described above performs tracking by the wobble signal of the AC component detected from the bent form recorded in all tracks over the data area and the header area, not the DC signal. Is performed without being suspended, and there is a difference in the amount of light detected from the data area and the header area, but the tracking error signal is calculated by the sum signal of the left and right detection signals, ignoring the component corresponding to the DC component. Even when the area is switched to the header area, the magnitudes of the left and right detection wobble signals are changed at the same ratio, so that the tracking can be made stable even when the area is switched.

Also, unlike in the case of the phase inversion of the wobble signal detected left and right according to the switching of the land and the groove, the intended phase inversion on the recording surface of the same type (land or groove) is formed, in the embodiment of FIG. When the output signal of the subtractor 103 and the adder 104 is directly multiplied and used as the tracking error signal Te, the signals ⑤ and ⑥ in FIGS. 13A to 13C can be obtained. It is also possible to perform stable tracking.

FIG. 15 shows an overall configuration diagram of recording a signal in a data area of a recordable optical recording medium according to the present invention and reproducing the signal therefrom while performing accurate tracking as described above. FIG. A focus control unit for performing focus adjustment with the DC component of the signal detected by the optical signal pickup unit 1, the control signal generator 100, the tracking controller 200, and the control signal generator 100, 300); A section recognizing unit 400 recognizing a header region existence section from the low frequency wobble signal separated and extracted by the control signal generator 100 and outputting a header section signal; A reproduction signal processing unit (110) for filtering and outputting a signal to filter the original recording data from the high frequency output signal of the control signal generator (100) based on the header section signal; A recording signal processing unit 500 which determines a recording time point of the input data based on the header section signal, converts the data into a pit signal, and outputs the converted pit signal; And a recording light control unit 510 for adjusting a recording light incident time of the optical pickup 1 by the converted pit signal.

In Fig. 15, illustration of the configuration related to reference clock generation or the like necessary for recording / reproducing is omitted.

In the optical recording medium recording / reproducing apparatus configured as shown in FIG. 15, the section recognizing unit 400 identifies a section of the header area from the wobble signal detected by the control signal generating unit 100 and outputs a header section signal accordingly. The recording and reproducing process is performed in the same manner as before, except that the recording position and the recording time of the input data and the retrieval time of the recording and reading of the recorded data are made. A configuration block of header section recognition and its operation will be described in detail centering on the section recognizer 400 that recognizes an existing section of the region and outputs a header section signal.

FIG. 16 is a detailed configuration diagram showing in detail the entire configuration for accurately outputting a section signal in a predetermined state by recognizing a header region from an optical recording medium according to the present invention. FIG. 16 shows the left and right photodiodes PDa and PDb for detecting left and right reflected light. ; Low pass filters 101a and 101b for passing only the low wobble signal components from the left and right signals detected; A slicer 401 for shaping a wobble signal component that is passed through and amplified after the amplification into a pulse shape; An edge detector 402 for detecting an edge of the output pulse signal; A phase lock unit (PLL: Phase Lock Loop) 410 for outputting a pulse synchronized with the phase of the detected edge; A divider 411 for dividing the pulse synchronized by the phase synchronizer 410 into two; A multiplier (412) for multiplying the divided signal by the normalized pulse of the slicer (401); A mux 414 for selecting the multiplied signal or its inverse signal; A mono-stable multi-vibrator 415 (hereinafter referred to as mono multi) that outputs a predetermined period of time by the edge of the signal selected by the mux 414; And a T-flip-flop 416 whose output value is inverted at the output edge of the mono multi 415 based on the state of the signal selected by the mux 414.

FIG. 17 is a waveform diagram showing waveforms of a main part in the apparatus for outputting a header section signal of FIG. 16. FIG. 17A shows a state of a header section signal initially outputted as a section and a desired state (HIGH). 17B illustrates a process of automatically calibrating the state when the state of the header section signal that is recognized in the section and initially outputted is not a desired state. Hereinafter, referring to the waveform diagram of FIG. 17. The operation of the section recognition unit 400 of FIG. 15 will be described in detail.

First, when both signals are subtracted from each other after being amplified after passing through the low pass filters 101a and 101b, the signals are inverted in phase as described above. do. In this way, the low frequency signal with the increased signal size is converted into positive (+) and negative (-) pulse signals by the slicer 401 up and down by a predetermined reference (slice level) as shown in ① of FIG. 17A. However, when the shape of the phase reversed to the bent signal shape is before and after the header area as shown in FIG. 5, the state is not changed at the time point t0 corresponding to the point and the same state is maintained by one pulse section T. It will last.

On the other hand, the edge detector 402 outputs a clock signal of twice the frequency that is switched to the rising edge every time the rising and falling edges of the pulse by the slicer 401 as shown in ② of FIG. 17A. However, at the time of detection (t0) corresponding to the phase inverted point, since no state transition occurs and no edge is generated, clock generation is suppressed at this point. In this manner, a clock signal twice as large as the wobble signal is generated. A continuous clock signal outputted from the edge detector 402 and phase locked to the output clock is outputted from the phase synchronizer 410 as shown in FIG. 17A.

The output clock of the phase synchronizer 410 is divided by two by the divider 411 so that the detected and shaped wobble signal and the clock frequency are equal to each other. When the clock becomes in phase with the detected wobble signal before the phase inversion, the phases are reversed with each other after the phase inversion. Therefore, the output by the multiplier 412 multiplying the two signals results in the phase inversion time as shown in? The transition from high to low is made by t0).

On the other hand, the output line (Out) of the mux 414 is the inverse of the output of the multiplier 412 by the output state (Q) of the high (set) set during the initial drive of the T-flip-flop 416 If the signal is selected as an inverted signal, the signal applied to the clock input terminal of the mono-multi 415 becomes an inverted signal of the output of the multiplier 412 as shown in ⑤ of FIG. At (t0), the signal is switched from low to high, and the signal switching of the clock input stage causes the mono-multi 415 to recognize the header area at a predetermined time (T1) as shown in (6) of FIG. 17A. It is set longer than the width of the header section signal for.

As described above, when the signal state of each part is maintained and the bent phase inversion on the optical recording medium is detected again, the output pulse of the slicer 401 and the frequency divider 411 at the time t1. Since the output pulse is in phase again, the output of the multiplier 412 is inverted from low to high, and the output of the mux 414 is inverted from high to low, and the mono-multi ( While the output state of 415 is inverted high again, it is clocked into the T-flip flop 416, but at this time, the output state of the mux 414 is already turned low, and the output of the mux 414 is output. Since the signal is input to the operation enable terminal of the T-flip flop 416 to maintain the disabled state, the output value Q of the T-flip flop 416 is not inverted, and the state thereof is not inverted. Will remain the same, and thus the mux 414 As output signals, you'll have a header area signal to output a predetermined high level by the detection section of the header area.

However, if the clock signal synchronously oscillated by the phase synchronizer 410 is 180 degrees out of phase with the output clock of the edge detector 401 as in ② of FIG. 17B, the output clock of the divider 411 is Since the phase is inverted from the output clock of the slicer 401 before the phase inversion in the bent form, and in phase with each other after the phase inversion in the bent form, the output signal of the multiplier 412 is the header as shown in ④ of FIG. 17B. Before the phase inversion of the bent signal informing the section of the region, the state is inverted to a high state.

Also at this time, the output value Q remains high due to the setting at the time of initial driving of the T-flip flop 416 so that the selected output value of the mux 414 becomes the output of the multiplier 412 output. Since the signal is a butted signal, a signal inverted from high to low is input to the clock terminal of the mono-multi 415 at the time of detecting the phase inversion t0, and at the same time, a header region section signal having a low state is output to the outside. An error condition occurs. However, when the time t1 at which the bent phase inversion is detected again, the output of the multiplier 412 is inverted from high to low, and the inverted signal through the mux 414 is inverted from low to high. The mono-multi 415 causes the output state to remain low for a predetermined time T1.

When the output time of the mono-multi 415 returns to high again after the predetermined time has elapsed (t2 in FIG. 17B), the output state of the mux 414 at this time is in a high state as shown in ⑤ in FIG. 17B. Thus, the edge of the mono-multi 415 returning to the output state causes the T-flip-flop 416 to toggle its output state as shown in FIG. 17B. Therefore, the state initially set to the high state to cause the mux 414 to output the inverted signal of the output of the multiplier 412, the output value (Q) of the T- flip-flop 416 is low By switching, the mux 414 is calibrated to output an uninverted signal of the output of the multiplier 412, after which the output of the multiplier 412 is directly output as a section signal of the header area. Accordingly, in the section in which the header region is recognized, the header section signal in which the predetermined high state is output can be obtained.

Accordingly, the reproduction signal processing unit 110 of FIG. 15 uses the high frequency signal inputted based on the header section signal detected and outputted according to the above process to convert the waveform of the header signal which is the position information of the user data signal and the optical recording medium. After shaping and processing the signal, the output signal is separated into a reproduction data signal and a position information signal, and the recording signal processing unit 500 controls the recording surface of the corresponding position to be recorded by the optical recording medium position information obtained by the separation output. When identification is confirmed by (not shown in the drawing), the recording data is started to be recorded through the recording light control unit 510 in synchronization with the end point of the header section signal.

The optical recording medium according to the present invention configured as described above further improves the recording density of the signal by further reducing the track length of the header area and increasing the track length of the recording surface, and the header area together with the bent shape of the data area. By providing a recording / reproducing apparatus and a method using the header signal in a bent form and using the same, stable and accurate tracking can be performed without interruption of tracking over all tracks, thereby recording the signal and recording of the recorded signal. It is a very useful invention that enables more stable and faster data access by eliminating error recovery or reread and rewrite times by reducing the probability of recording and reproducing errors of signals that may be caused by tracking errors in the detection process.

1 shows a plane and a cross section of some tracks including a header area in a conventional recordable optical record carrier record carrier,

FIG. 2A shows some tracks in which the shape of the recording surface is switched back and forth in the header area in one embodiment of the optical recording medium according to the present invention, and FIG. 2B shows wobble of periodicity detected according to the track path of FIG. 2A. Shows a signal,

Fig. 3 shows some tracks in which the shape of the recording surface is not switched with the header area back and forth in one embodiment of the optical recording medium according to the present invention.

4A and 4B show, in another embodiment of the optical recording medium according to the present invention, some tracks in which bent recording feet are formed at positions displaced from one another on adjacent header tracks between adjacent tracks,

Fig. 5 shows some tracks in which the shape of the recording surface is switched with the phase inversion point on the travel path and the header area back and forth in another embodiment of the optical recording medium according to the present invention.

6A to 6B show some tracks in the case of another embodiment of the optical recording medium according to the present invention, in which the shape of the recording surface is reversed with the phase inversion point on the travel path and before and after the header area. One,

7 is a block diagram showing an embodiment of an apparatus for forming an optical record carrier according to the present invention;

8 shows a light control signal applied to the apparatus of FIG.

FIG. 9 shows an approximation of an optical record carrier and a track on a medium according to the present invention formed by the apparatus of FIG.

FIG. 10 shows a schematic configuration for tracking an optical recording medium and reproducing a recording signal based on the same according to the present invention;

FIG. 11 is a detailed configuration diagram illustrating a control signal generation unit for tracking control of FIG. 10 in more detail.

FIG. 12 illustrates signal waveforms of the tracking control unit of FIG. 11 during operation of the servo system of FIG.

FIG. 13 illustrates waveforms of a main part generated when the control signal generator for tracking control of FIG. 11 performs a tracking operation, in which 11a is a waveform diagram during normal center tracking and 11b is biased to the right in the advancing direction. Is a waveform diagram of, and 11c is a waveform diagram when the signal is biased leftward,

Fig. 14 shows some exemplary tracks for explaining the principle of detecting a phase inverted signal from both sides in which the recording surface is bent in phase;

Fig. 15 shows the overall configuration of an apparatus for tracking and recording signals and reproducing signals from the optical record carrier according to the present invention;

16 is a detailed block diagram of an apparatus for recognizing a header area of an optical record carrier according to the present invention;

FIG. 17 is a waveform diagram illustrating waveforms of respective parts in a process in which the section recognizing apparatus of FIG. 16 recognizes a header region and outputs or corrects a header section signal in a predetermined state from the header region.

※ Explanation of code for main part of drawing

G: Groove L: Land

PDa, PDb: Photodiode 1: Optical Pickup

10 laser 11 collimator

12a, 16: semi-transparent mirror 12b, 14b, 16a, 16b: reflective mirror

13a, 13b: Acoustic Optical Modulator

15a, 15b: Acoustic Optical Diffractor

17 condensing lens 20 wobble forming signal generator

100: control signal generator 101a, 101b: low pass filter

102a, 102b: high pass filter 103: subtractor

104: summer 105: multiplier

200: tracking control unit 201: tracking compensation unit

202: optical pickup drive unit 110: reproduction signal processing unit

300: focus control unit 400: section recognition unit

106, 401: slicer 107, 402: edge detector

108, 410: phase synchronizer (PLL) 109, 411: divider

412 multiplier 413 inverter

414: multiplexer 415: monostable multivibrator

416: T-flip-flop 500: recording signal processing unit

510: recording light control unit

Claims (24)

A recording area in which a bent signal having a period is recorded; And And a header area recorded in a form in which a header signal is bent between the recording areas. And the bent form of the header signal has the same period as that of the bent signal. The method of claim 1, The bent form of the header signal is formed over the entire area of the header area. The method of claim 1, And the bent signal includes a recognition signal informing the header area at a predetermined position. The method of claim 3, wherein The recognition signal is an optical recording medium, characterized in that the phase of the bent signal is inverted. The method of claim 1, And the phase of the bent signal is inverted at a boundary between the header area and the recording area. The method of claim 1, And wherein the bent shapes of the header signals on neighboring tracks have inverted phases. The method of claim 1, The curved header signal is formed at a predetermined distance from one recording area, wherein the position of the header signal between adjacent tracks is formed so as to be mutually shifted. A recording area in which a data signal is recorded; And It is configured to include a header area in which the header signal is recorded, Wherein the recording area and the header area each have a bent signal, wherein the bent signal is formed over the entire header area. Low-band signal detecting means for detecting a bent signal component having a period from a data area and a header area of the optical record carrier; And And a header position detecting means for detecting the position of the header area from the detected bent signal. Signal detecting means for detecting a bent signal component having a period from a data area and a header area of the optical record carrier; And And tracking means for performing tracking in accordance with the detected bent signal component. Signal detecting means for detecting a plurality of bent signal components having periods from a data area and a header area of the optical record carrier; Error signal generating means for generating a tracking error signal by calculating the plurality of detected signal components; And And position control means for correcting the position of the optical pickup based on the generated error signal. Optical recording / detecting means for injecting recording light onto the optical recording medium to record data and to detect a signal recorded by reflected light of the read light; Reproduction signal detection means for separating and extracting a bent signal having a data signal and a period from the detected signal; Tracking means for controlling the tracking of the optical recording / detecting means from the separated and extracted bent signal; Section signal generating means for detecting the position of the header area on the optical recording medium from the bent signal to be separated and extracted and generating and outputting a section signal corresponding thereto; Reproducing means for restoring the separated and extracted data signal based on the time period of the output section signal; And And recording means for applying to the optical recording / detecting means recording light corresponding to the input data based on the time zone of the output section signal. Signal generating means for generating a bent signal having a period; Light transmitting means for selectively transmitting incident light according to an input hair signal; Path deflection means for deflecting the advancing path of the selective transmitted light according to the generated bent signal; And And recording means for recording the form of the selective transmitted light at the incident point of the deflected optical path. Detecting a bent signal component having a period from a data area of the optical record carrier; A second step of detecting a predetermined change in a signal in the detected bent signal component; And And a third step of outputting a header section signal notifying the existence of the header area from the point of change. Detecting a bent signal component having a period from a header area of the optical record carrier; A second step of detecting a predetermined change in a signal in the detected bent signal component; And And a third step of detecting and reproducing data in the data area from the point of change. Detecting a bent signal component having a period from a header area of the optical record carrier; A second step of detecting a predetermined change in a signal in the detected bent signal component; And And a third step of recording data in the data area from the point of change. A first step of continuously detecting a bent signal component having a period from a data area and a header area of the optical record carrier; Calculating a deviation amount of the detected bent signal component; And And a third step of correcting the position of the optical pickup according to the calculated amount of deviation. Selectively transmitting incident light according to an input header signal; A second step of deflecting a propagation path of the transmitted light according to a bent signal having a period; And recording a form according to the selective transmitted light at an incident point of the deflected optical path. A recording area in which a wobble signal having a period is recorded: and And including a header area in which a header signal is recorded in a wobble form between the recording areas. The wobble signal includes an identification signal for informing the header area at a predetermined position. The method of claim 19, The recognition signal is an optical recording medium, characterized in that the phase of the wobble signal is inverted. The method of claim 19, The wobble form of the header signal has the same period as that of the wobble signal. A recording area in which a wobble signal having a period is recorded; And The header signal is envisioned between the recording areas including a header area recorded in a wobble form. And the phase of the wobble signal is inverted at a boundary between the header area and the recording area. A recording area in which a wobble signal having a period is recorded; And The header signal is envisioned between the recording areas including a header area recorded in a wobble form. The wobble form of each header signal on an adjacent track has an inverted phase. A recording area in which a wobble signal having a period is recorded; And The header signal is envisioned between the recording areas including a header area recorded in a wobble form. The wobble header signal is formed at a predetermined distance from one recording area, and the position of the header signal between adjacent tracks is formed so as to shift from each other.